This is a new shared instrumentation grant to purchase a PHILIPS CM 100 transmission electron microscope with a computer interface and high resolution digital camera system (Advantage CCS-Plus). The core user group consists of five faculty members of the Center for Molecular and Behavioral Neuroscience and the Department of Biological Sciences at Rutgers-Newark who are experienced light and electron microscopic neuroanatomists. These five scientists and their laboratory staffs ( a total of more then 25 researchers) presently share the use of a single electron microscope, a Philips CM-10 located in Boyden Hall, with all the other researchers at the Rutgers-Newark Campus. The CM-10 is approximately 1- years old and is the only electron microscope on the Newark Campus. The new instrument would be placed in Boyden Hall and the existing Philips CM-10 will be trade-in. Since the floor plan for the new electron microscope is the same as for the existing one, no extra costs are involved to install the equipment. Many of the features of the requested microscope, not available on the CM-10, would enhance substantially research productivity. The Philips CM 100 is a state-of-the-art modern electron microscope with excellent optics and a user-friendly computerized interface. The 5-axis motorized computer-controlled stage allows recall of up to 100 specific grid positions with high accuracy which eliminates the need for searching grids manually to return to previously examined positions. The high resolution digital camera system (2K x 2K pixels) obviates the need for relying on conventional film for many or most applications. The on-screen measurement function for online measurements of image morphologies and subsequent storage of these measurements for statistical evaluation in the user~s laboratory will speed data acquisition by greatly reducing photography. In addition digital images allow for rapid image transfer and analysis via a built-in Ethernet network linked to users desktop computers as well as to a newly installed supercomputer (IBM SP2) affording a great savings in time, photographic cost and enhanced teaching capabilities. The electronic image archiving and analysis system will also augment the ability of our researchers to communicate our data via the Internet with collaborators at remote locations.